The present invention relates to a wrist watch type receiver of fish sonar for being able to see the state of the sea.
Generally, telecommunication apparatus is known in which very high frequency signals from a transmitter attached to a buoy of a stationary fish net in the sea are received by a receiver at a remote seashore, the transmitter having an ultrasonic transmitting-receiving vibrator and an echo signal transmitting portion.
However, in this telecommunication apparatus, the state of the sea, of a near portion of a fishing boat or a quay is not seen at hand.
When many fishermen fish using a fishing boat having a fish sonar, even if some fishermen near the display device of the fish sonar can see the state of the sea, the other fisher men cannot see the state of the sea.